BuddyPress.org

I’m running BuddyPress on a WP 3.0 Multisite, and I’m listing activity entries on blog pages on those subdomains.
Posting activity entries from subdomains and listing them on subdomains work ok, and if I go to the permalink for a single entry I can read it and reply to it, this takes place under the main blog address.
The issue I’m trying to resolve is when I click to reply to an entry right in the list of entries on a blog on a subdomain. The entries are listed, but when I click to reply I briefly see a reply posting field appear, but then it disappears in a fraction of a second, and the page scrolls a few lines down but no reply posting form is visible anymore. This seems very puzzling to me, I need a little help figuring it out.

I’m wondering if this is related to the subdomain being just that, a subdomain with f.ex. http://blog.site.com instead of the main domain at f.ex. http://site.com.
Any ideas on how I can make the reply form work on subdomain blogs?